A New Genus and Species of Nine-Primaried Oscine of Uncertain Affinities from Peru
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THE AUK A QUARTERLY JOURNAL OF ORNITHOLOGY VoL. 93 J•JL¾1976 No. 3 A NEW GENUS AND SPECIES OF NINE-PRIMARIED OSCINE OF UNCERTAIN AFFINITIES FROM PERU G•ORG• H. LoweRY, JR., ^•r• D^• A. T^LLM^• T• frequencywith which hitherto unknown genera and speciesof birds have continued to turn up in Peru in recent years is indeed remarkable. Among the noveltiesdiscovered and duly describedsince 1964 are 2 new generaand 10 new species•, someof which have been spectacular(for example, the tanagers Buthraupis aureodorsalisand Wetmorethraupissterrhopteron). Also now in preparationby personnel here at this .museumand by avian systematistsat other ornithological centers are descriptionsof at least 6 additional new species(an owl, 2 hummingbirds,2 flycatchers,and a wren). This paper describesstill another recent Peruvian discovery, a bird that we call the "Pardusco," becausethat is the name applied to it by our Peruvian field assistantswho live near the region where it is now known to occur. An adult male and an immature male were obtained in June 1973 and 8 additional specimens(5 males and 3 females) were taken in June 1974, by our resident assistant Manuel Villar, while a memberof our field parties of those years. And, finally, in January, June, and July 1975, the remainingspecimens, 22 males and 15 females, were procuredby another one of our field parties, composedof Villar, Robert S. Kennedy, Carol S. O'Neill, Theodore Parker, III, and Reyes Rivera A. All encounters with the bird have been in the isolated and semi-isolatedwooded tracts of low trees and shrubs (elfin forest) near the crest of the Carpish Ridge of the eastern cordillera of the Andes in the Departamento de Hu&nuco, above Acomayo. It is the region in •Synallaxis courseni Blake, Percnostola macrolopha Berlioz, Grailaria eludens Lowery and O'Neill, Conioptilon mcilhennyi Lowery and O'Neill, tlemispingusparodi• Weske and Terborgh, Hemispingusrufosuperciliarls Blake and Hocking, Buthraupls aureodorsalisBlake and Hocking, Wetmorethraupis sterrhopteron Lowery and O•Neill, Cacicus koepckeae Lowery and O'Neill, and Agelaius xanthophthalmus Short. 415 The Auk 93: 415-428. July 1976 P•a•DreSCO,Nephelornis oneilli A NEW OENI, J$ AND $I•ECI1•$ rRO• I•]•RU From a watercolor painting by John P. O'Neill 416 Low•a¾ ^up T^LLM^N [Auk, Vol. 93 which Buthraupis aureodorsalisand Hemispingusrufosuperciliaris were discoveredand is still the only location from which they are known. These same woodlandsare inhabited by Ampelion [Doliornis] sclateri, a speciesof cotingaknown until 3 yearsago only from 2 old spedmens from the Departamento de Junin but now found to be fairly common above Acomayo in suitable habitats. That this regionhas yieldedsuch unexpected discoveries is surprising, for it lies in a part of Peru that must be consideredone of the better known sectionsof the republic. In 1922 and 1923 John T. Zimmer passedthrough or within easy striking distanceof the forest that these speciesfrequent (see Zimmer 1930), and our own field parties in the 1960'sand early 1970'slikewise often operatedwithin sight of the same forest. One can only speculatehow many more such ornithological treasure-trovesawait discoveryin the ruggedmassifs of the Peruvian Andes. From the outset,we have consideredthe Parduscoto be a bird of uncertain familial relationships.For reasonsstated beyond, we cannot affiliate it with any known genusof tanager, honeycreeper,or finch. Becauseof certain morphologicalpeculiarities, mainly ones pointed out to us by Walter J. Bock followinghis study of a skeletonand a wet- preservedspedmen we were able to supplyhim, we feel compelledto erect for it a new genusand to leave its familial placementto the outcome of further studies. Nephelornis gen. nov. TYPz-sPzcms: Nephelornis oneJill Lowery and Tallman. DIAGNOSIS:A small, nine-primaried oscinewith the wing formula 6 > 7 > 5 > 4 > 8 > 3 > 2 > 1 > 9; wing longer than tail, with the ratio approximately 1.16:1.00; tail slightly graduated,with the central rectricesthe longestby approximately 6 to 8 ram; shapeof rectricesmoderately broad and terminallyrounded; culmen distinctly arched; bill small in overall size and approximately half as deep and as wide at the base as it is long; tomium decurved and with a barely perceptiblerhamphothecal subterminalindentation that would hardly qualify as a notch; nostrils fully exposed, roughly oval in shape,and with the superiorhemisphere of each overhungby a membrane; rictal bristlesrather long but weak; a few bristleson the chin and face; toes and the laminiplantar tarsometatarsusconspicuously strong; middle toe (no. III) longest and length without claw more than half that of the tarsometatarsus; toe no. IV without claw slightly longer than toe no. II without claw and both shorter than hind toe (no. I); hind claw fully twice the size and length of the other claws; skull fairly typical of nine-primaried oscines(Fig. 1A and B) with no diagnostic palatal or mandibular features but in general shape and proportions readily separable from the skull of any genus with which it has been compared, includingHemispingus, Chlorospingus, Xenodacnis, Diglossa, Conirostrum, Iridophanes, and a wide array of emberizine finches; the tongue slightly frilled with the lateral edges raised to form a shallow groove (Fig. 2A); the basihyale flattened, as is July 1976] The Pardusco 417 A B C Fig. 1. Skull of Nephelornis oneilli LSUMZ 80122). (A) Lateral view with mandible in position. (B) Ventral view without mandible. (C) Lateral view of basihyale and proximal end of ceratobranchiale.(D) Schematiccross section of basihyaleat its approximatemidpoint. Drawings by Dorothea Goldys. typical for nine-primariedoscines (Figs. 1C and D); a small slip of M. tracheo- lateralisinserting onto the proximal end of the ceratobranchiale,a conditionseen in many passerinebirds but lost in most nine-primaried oscines(Figs. 2B and 3A and B); M. hypoglossusanterior present,a conditionfound in many passerinesbut lost in most, if not all, nine-primariedoscines (Figs. 3A and C); the M. cerato- hyoideustaking origin partly from the medial surface of the ceratobranchialeas is 418 LOWERY' AND TALLMAN' [Auk, Vol. 93 tr h B hg o gg mh Msth bm 'Msh Fig. 2. Tongue apparatusof NephelornisoneJill (LSUMZ 77650). (A) Dorsal view of the corneoustongue to the frilled tip and slightly upturned lateral edges. (B) Ventral view of the entire tonguemusculature in placein the head; the iV[ s h and M m h have been removed on the right side. Abbreviations: branchiomandibularis;M c g : M. ceratoglossus;M c h : iV[. ceratohyoideus; M g g •-• iV[. genioglcssus;M hg a = iV[. hypoglossusanterior; iV[ hg o hypoglossusobliquus; M m h = M. mylohyoideus;M s h : iV[. serihyoideus; iV[ st h : iV[. stylohyoideus;M th h = iV[. thyreohyoideus;iV[ tr h: M. tracheo- hyoideus;M tr 1 = iV[. tracheolateralis.Drawings by Dorothea Goldys. usual for most passerinesand for nine-primariedcscines in particular, but also taking its origin partly from the lateral surface of the ceratobranchiale,a feature that may be unique among nine-primariedoscines (Figs. 2B and 3A and B). COLO•.ATtoZV:The only spedes presently known is rather nondescript, mostly plain brown without streaks, spcts, distinct wing bars, a superciliary line, or any facial marks. July 1976] The Pardusco 419 st h bm M trh hg o M tr Ix hg a gg M thh • cg Mc ch tr h cg c gg bm 'M hg a M hgo Fig. 3. Tongue apparatus of Nephelornis oneilli (LSUMZ 77650). (A) Ventral view of the entire tongue musculature removed from the head and spread out to show the musclesclearly. (B) Dorsal view of the right hyoid horn showing the musclesattached to it. (C) Ventral view of the paired paraglossaliashowing the musclesattached to it. SeeFigure 2 for abbreviations.Drawings by DorotheaGoldys. 420 LOWERY AND TALLMAN [Auk, Vol. 93 Fig. 4. A Pardusco[oHowing its capturein a mist net at BosqueUnchog. Photo by R. S. Kennedy. Sr.zc•s: No obvioussexual dimorphism but femalesaverage slightly smaller and weigh less than do males. Nephelornis oneJill sp. nov. P•u•usco TYPE: Adult male (skull fully ossified);Louisiana State UniversityMuseum of Zoologyno. 81114; BosqueUrichog, on passbetween Churubamba and Hacienda Paty aboveAcomayo, 09o41 ' S, 75ø07' W, elevationapproximately $$92 meters• July 1976] The Pardusco 421 kms Fig. 5. Map of the Acomayoarea of the Departamentode Hu•nuco•Peril, show- ing the locationof place-namesand physicalfeatures mentioned in the text. Depto. Hu•nuco, Peril; 16 July 1975; collectedby TheodoreParker, III; original number 922. DmG•os•s: Same as for the genus,of which it is the only known member. DEscmPT•o• oF HOEOTYP•: General color wholly brownish; entire dorsum Mummy Brown (capitalizedcolor namesare from Ridgway 1912); primariesand secondaries Blackish Brown (3), faintly edged anteriorly with Tawny-Olive; greater secondary covertsdull brown, with Ochraceous-Tawnyterminal edgingsthat form an indistinct wing bar; upper surfaceof rectricesBlackish Brown, with outer web narrowly edged 422 Low• AND TALLMAN [Auk, Vol. 93 Fig. 6. A panoramicview of BosqueUnchog, the forestedarea on the ridge in center and left side of photograph. The woodlandsbelow the crest of the ridge is one of the habitats where Nephelornisoneilli is presentlyknown to occur. The low area at the base of the woodlands is the pass between Churubamba and Hacienda Patjr. White lines are the trails followed almost daily by LSUMZ personnelduring their visits; X, a few of the placeswhere specimensof the specieswere taken; O, some additional sites where the specieswas observed; star,